Kinetic Study on the Solvent Floatation of Reactive Dyestuff and Its Direct Photometric Determination in the Organic Phase

It was found by the kinetic study of solvent floatation of reactive dyestuff (taking the reactive scarlet red X-3B as an object in the study),that under a relatively low flow-rate,the increase of speed constant was directly proportional to the flow-rate of the floatation gas (i.e.nitrogen),and in the course of solvent floatation,the relationship between -ln(At/A0) and t was in conformity to the 1st order kinetic equation.Rate of extraction of 3 different reactive dyestuffs separated by the solvent floatation was determined in mixtures,the values obtained were all over 96%.The solvent floatation was proved to have large multiple factor of enrichment,high recovery and less consumption of solvents,as compared with the conventional solvent extraction.The reactive dyestuff floated in the organic phase was determined directly in it by photometry.A sample of waste water from a dyeing mill was analyzed by the proposed method for the content of scarlet red X-3B,giving values of floatation rate and recovery of 98.1% and 93.6% respectively.